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    <script>
        // ['1', '2', '3'].map(parsenInt)相当于下面这样写
        var ary = ['1', '2', '3'].map((item, index) => parseInt(item, index))

        console.log('ary', ary);

        console.log('parseInt("2",1)转换', parseInt('2', 1));
    </script>

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